The present disclosure relates generally to techniques for performing wellsite operations. More specifically, the present disclosure relates to techniques, such as blowout preventers (BOPs), packers, and/or ram blocks, for sealing wellbores.
Oilfield operations may be performed to locate and gather valuable downhole fluids. Oil rigs are positioned at wellsites, and downhole tools, such as drilling tools, are deployed into the ground to reach subsurface reservoirs. Once the downhole tools form a wellbore to reach a desired reservoir, casings may be cemented into place within the wellbore, and the wellbore completed to initiate production of fluids from the reservoir. Tubing (or pipes) may be positioned in the wellbore to enable the passage of subsurface fluids to the surface.
Equipment, such as blowout preventers (BOPs), may be positioned about the wellbore to form a seal about the tubing therein to prevent leakage of fluid as it is brought to the surface. In some cases, the BOPs employ rams, ram blocks, and/or seals that engage a tubular in the wellbore and/or seal the wellbore. Examples of ram and/or ram blocks are provided in U.S. Patent/Application Nos. 2008/0265188, 2012/0012340, 2012/0012339, and 2010/0243926, the entire contents of which are hereby incorporated by reference herein.